1. Field of the Invention
This invention relates to a positive-displacement piston mechanism having a rotary piston structure.
2. Description of Related Art
A positive-displacement piston mechanism which has a reversible relation with internal combustion engines, such as a pump, a blower, a compressor and the like, including a vane type rotary mechanism having a rotary piston structure, has been already utilized. For example, in a a rotary blower shown in FIG. 8, blades (5) are biasedly arranged for flexibly moving in radial slots (4) of a rotor (3) provided in a circle-shaped chamber portion (2) of a squared box (1). Then, the air and/or other fluid are pushed out from an inlet into an outlet by the blades (5) flexibly moving in the slots (4) of the rotor (3) rotating at high speed and increasing the pressure by centrifugal force inside of the circle-shaped chamber portion (2).
There are difficult technical problems associated with a vane type rotary mechanism mentioned above, including abrasion at the edges of the vanes, and difficult obtainment of airtightness and smooth operation of a seal between the vanes and the chamber portion.